1. Field of the Invention
The invention relates to a wireless communications module, and more particularly to a wireless communications module in a multi-radio communication apparatus which is capable of compensating for frequency drift of a clock signal due to activation of other wireless communications modules co-located in the multi-radio communication apparatus.
2. Description of the Related Art
With the development of wireless communications technology, mobile electronic devices may now be equipped with more than one wireless communications module to provide different wireless communications services, such as a GSM (Global System for Mobile Communications), a WCDMA (Wideband Code Division Multiple Access), cdma2000, a WiMAX (Worldwide Interoperability for Microwave Access), a TD-SCDMA (Time Division Synchronous Code Division Multiple Access), an LTE (Long Term Evolution), a TD-LTE (Time Division Long Term Evolution), a Bluetooth, a Wireless Fidelity (Wi-Fi), and a Global Positioning System (GPS) wireless communications service, and any combinations thereof. In this regard, in the mobile electronic devices, there is more than one clock source configured to generate a local oscillating (LO) frequency which is utilized by each wireless communications module for generating radio frequency (RF) signals to be transmitted to an air interface, and/or down converting RF signals into intermediate frequency or baseband signals for further signal processing.
However, because integrated circuits (ICs) continue to shrink in size, the placement distance between each wireless communications module has also shrunk, resulting in influence generated therebetween, such as clock frequency drift. Frequency drift is an unintended and generally arbitrary offset of an oscillator from a nominal frequency. For a radio transmitter and/or receiver, frequency drift can cause a radio station to drift to an adjacent channel, causing illegal interference. Because of this, a method for compensating for frequency drift and a communication apparatus utilizing the same is highly required.